SPDT switch with multiple contact arrangement

Abstract

An electrical switch includes a housing within which a stationary center contact arrangement is located. Spaced apart stationary first and second contacts are located on opposite sides of the center contact arrangement. A movable contact member is maintained in engagement with the center contact arrangement, and is selectively engageable with either the first stationary contacts or the second stationary contacts, in response to operation of an actuator mechanism associated with the housing. The movable contact member includes a unitary center contact area, in combination with a series of spaced apart first contact arms extending outwardly from the center contact area, and a series of spaced apart second contact arms extending outwardly from the center contact area. The first and second contact arms are selectively engageable with the stationary first and second contacts mounted to the housing, and the common center contact area ensures movement of the first and second contact arms in unison between respective first and second operative positions which establish connection with the respective first and second stationary contacts. The electrical switch is capable of being used as a transfer switch, for selectively supplying power to a single load from one of two power sources, each of which is interconnected with one of the sets of first and second stationary contacts.

I claim:  
     
       1. An electrical switch, comprising: 
       a housing;  
       a plurality of first contacts stationarily mounted to the housing;  
       a plurality of second contacts stationarily mounted to the housing and spaced from the plurality of first contacts;  
       a stationary center contact arrangement mounted to the housing between the first and second stationary contacts;  
       a movable contact member mounted to the housing and movable between first and second engaged positions, wherein the movable contact member includes a center contact area and first and second arms extending outwardly from the center contact area, wherein the center contact area is engaged with the stationary center contact arrangement, and wherein each of the first and second arms comprises a plurality of separate arm sections extending outwardly from the center contact area, wherein each of the arm sections of the first arm includes a contact area adapted to engage one of the plurality of first stationary contacts when the movable contact member is in the first engaged position, and wherein each of the arm sections of the second arm includes a contact area adapted to engage one of the plurality of second stationary contacts when the movable contact member is in the second engaged position; and  
       an actuator operably engaged with the movable contact member for moving the movable contact member between the first and second engaged positions.  
     
     
       2. The electrical switch of  claim 1 , wherein the stationary center contact arrangement comprises a pair of spaced apart center contacts, and wherein the center contact area of the movable contact member engages the spaced apart center contacts and spans therebetween. 
     
     
       3. The electrical switch of  claim 2 , wherein the housing and the center contact area of the movable contact member include a pivotable mounting arrangement for providing pivoting movement of the movable contact member between the first and second engaged positions. 
     
     
       4. The electrical switch of  claim 3 , wherein the pivotable mounting arrangement comprises a pair of laterally extending tabs, wherein each of the tabs extends outwardly relative to one of the spaced apart center contacts, and retainer structure associated with the housing for receiving the tabs therebetween. 
     
     
       5. The electrical switch of  claim 2 , wherein the arm sections of the first arm and the arm sections of the second arm are spaced apart from each other, and wherein the center contact area of the movable contact member extends across the space between the arm sections of each of the first and second arms. 
     
     
       6. The electrical switch of  claim 5 , wherein the center contact area of the movable contact member and the arm sections of each of the first and second arms are formed integrally with each other. 
     
     
       7. The electrical switch of  claim 6 , wherein the movable contact member comprises a unitary rocker member formed of a conductive material, and wherein the contact areas of the first and second arms comprise a plurality of contact members carried by the unitary rocker member. 
     
     
       8. The electrical switch of  claim 7 , wherein the center contact area of the movable contact member is in the form of a V-shaped member engaged with the spaced apart center contacts, and wherein the arm sections of the first and second arms extend outwardly in opposite directions from the V-shaped center contact area. 
     
     
       9. In an electrical switch including a plurality of stationary first contacts and a plurality of stationary second contacts spaced apart from each other and a center contact arrangement located therebetween, in combination with a movable contact member and an actuator operably engaged with the movable contact member for moving the movable contact member between first and second engaged positions, the improvement wherein the movable contact member comprises: 
       a center contact area engaged with the stationary center contact arrangement;  
       a plurality of separate first arm members extending outwardly from the center contact area in a first direction, wherein each of the first arm second members includes a contact area for engaging one of the plurality of stationary first contacts when the movable contact member is in the first engaged position; and  
       a plurality of separate second arm members extending outwardly from the center contact area in a second direction opposite the first direction, wherein each of the second arm members includes a contact area for engaging one of the plurality of stationary second contacts when the movable contact member is in the second engaged position.  
     
     
       10. The improvement of  claim 9 , wherein the center contact arrangement comprises at least a pair of spaced apart center contacts, and wherein the center contact area of the movable contact member spans between and engages the pair of spaced apart center contacts. 
     
     
       11. The improvement of  claim 10 , wherein the plurality of separate first arm members and the plurality of separate second arm members, which extend outwardly from the center contact area, are formed integrally with the center contact area. 
     
     
       12. The improvement of  claim 11 , wherein the center contact area comprises first and second intersecting planar center contact sections, wherein the first arm members comprise outward extensions of the first planar center contact section and the second arm members comprise outward extensions of the second planar center contact section. 
     
     
       13. The improvement of  claim 12 , wherein the first arm members and the second arm members are coplanar with the first and second planar center contact sections, respectively. 
     
     
       14. The improvement of  claim 11 , wherein the actuator comprises a movable actuator body and a plurality of biased plunger members, wherein each of the plunger members is engageable with the center contact area and with a separate one of the first arm members to position the movable contact member in the first engaged position, and with a separate one of the second arms members to position the movable contact member in the second engaged position. 
     
     
       15. The improvement of  claim 9 , further comprising a retainer arrangement interposed between the movable contact member and a housing defined by the electrical switch, wherein the retainer arrangement is operable to maintain the center contact area of the movable contact member in engagement with the center contact arrangement during movement of the movable contact member between the first and second engaged positions. 
     
     
       16. The improvement of  claim 15 , wherein the first and second arm members are formed integrally with the center contact area of the movable contact member, and wherein the retainer arrangement comprises a pair of retainer tabs extending outwardly from opposite ends defined by the center contact area, in combination with spaced apart pairs of ribs defined by the housing, wherein each of the retainer tabs is located between one of the pairs of ribs, wherein the retainer tabs and the pairs of ribs cooperate to control movement of the movable contact member between the first and second engaged positions and to maintain the center contact area of the movable contact member in engagement with the center contact arrangement. 
     
     
       17. An electrical switch, comprising: 
       a housing;  
       a plurality of stationary first contacts mounted to the housing;  
       a plurality of stationary second contacts mounted to the housing and spaced from the stationary first contacts;  
       a stationary center contact arrangement mounted to the housing and located between the stationary first and second contacts;  
       a movable contact member comprising a center contact area engaged with the stationary center contact arrangement, a plurality of first arms interconnected with the center contact area and extending outwardly therefrom, wherein each of the first arms includes a contact adapted to engage one of the plurality of stationary first contacts when the movable contact member is in a first position, and a plurality of second arms interconnected with the center contact area and extending outwardly therefrom, wherein each of the second arms includes a contact adapted to engage one of the plurality of stationary second contacts when the movable contact member is in a second position; and  
       an actuator interconnected with the housing and engageable with the movable contact member, wherein the actuator is operable to move the movable contact member between the first and second positions.  
     
     
       18. The electrical switch of  claim 17 , wherein the plurality of first arms and the plurality of second arms are formed integrally with the center contact area. 
     
     
       19. The electrical switch of  claim 18 , wherein the center contact comprises intersecting first and second planar sections, wherein the plurality of first arms comprise spaced apart outward extensions of the first planar section and wherein the plurality of second arms comprise spaced apart outward extensions of the second planar section. 
     
     
       20. The electrical switch of  claim 18 , wherein the center contact arrangement comprises a plurality of spaced apart center contact members, wherein the center contact area extends between and engages the plurality of center contact members. 
     
     
       21. The electrical switch of  claim 18 , wherein the actuator is engageable with the movable contact member via a plurality of biased plunger members, wherein each of the plunger members is movable into engagement with one of the first arms to place the movable contact member in the first position, and is movable into engagement with one of the second arms to place the movable contact member in the second position. 
     
     
       22. The electrical switch of  claim 18 , wherein the movable contact member and the housing define cooperating engagement structure for maintaining the movable contact member in a predetermined position relative to the housing during movement of the movable contact member between the first and second positions. 
     
     
       23. The electrical switch of  claim 22 , wherein the cooperating engagement structure comprises a pair of tabs formed integrally with the center contact area and extending outwardly in opposite directions from opposed side areas defined by the movable contact member, and opposed pairs of spaced apart protrusions defined by the housing, wherein each of the tabs is adapted to be received between one of the pairs of spaced apart protrusions, wherein engagement of the tabs between the pairs of spaced apart protrusions functions to maintain the position of the movable contact member relative to the housing during movement of the movable contact member between the first and second positions.